12 Occupational Health of Animal Workers

Ben Hur P. Mobo, Peter M. Rabinowitz, Lisa A. Conti, Oyebode A. Taiwo

Some of the most intensive human-animal interactions occur in the occupational setting. Animal workers may encounter hundreds to thousands of animals each day, which increases the risk of exposure to biological, physical, and chemical hazards. In recent years a number of emerging infectious diseases have first appeared—as deadly outbreaks among workers with animal exposures. In addition to zoonotic disease risks, high rates of allergic disease, physical injuries, and psychological stress have also been reported in animal handlers. Many animal workers in both developing and developed countries are not enrolled in formal occupational safety and health programs or may receive medical care from human health care providers who are not familiar with the occupational risks these workers face.

Veterinarians have a special role to play in the development of occupational safety and health strategies for animal workers because they are intimately familiar with animal diseases and the necessary procedures involved in animal care and handling. Therefore improving occupational health and safety among animal workers represents a global health challenge that will require increased communication and cooperation between human health and animal health care providers.

This chapter outlines the occupational health hazards that animal workers encounter, presents a One Health team approach to worker health and safety that involves both human and animal health professionals, and suggests preventive health programs for particular worker groups.

Key Points for Clinicians and Public Health Professionals

Public Health Professionals

• Identify occupational groups in the community that have significant exposures to animals and work to educate them, local medical providers, and veterinary providers to ensure they receive appropriate preventive health services.

• Work with local petting zoos, county fairs, pet stores, and other organizations involved in human contact with animals in public settings to ensure that the guidelines of the National Association of Public Health Veterinarians (NAPHV) for Animals in Public Settings (http://www.nasphv.org/Documents/AnimalsInPublicSettings.pdf) are being followed. This will help protect both the public and workers in such settings.

Human Health Care Providers

• Ask patients whether they work with animals. If they do, assess their occupational risks.

• If asked to provide medical services (such as a preplacement physical) for a worker with animal contact, consider contacting the veterinarian responsible for the health of the animals in the workplace to discuss specific occupational risks.

• When evaluating a worker with an animal-related exposure (e.g., bite, scratch, mucous membrane contact), ensure that all potential zoonotic pathogens are being considered in the risk assessment and that prophylactic medication is started as necessary if indicated.

• When evaluating animal workers with acute or chronic illnesses, including asthma, dermatitis, and other allergic conditions, determine whether work exposures could play a causative role.

• If contracting to provide occupational health services to a group of workers with animal contact, employ a team approach to preventive care. The team should ideally include the veterinarian providing care to the animals as well as experts in exposure reduction such as an infection control/biosafety specialist and/or an industrial hygienist. This team approach will help ensure that relevant health risks in the workplace are being identified and addressed with adequate preventive services, including engineering controls, training, vaccination, postexposure protocols, and surveillance.

• Counsel immunocompromised and pregnant workers about particular risks of animal handling.

• Safeguard the confidentiality of any medical information about animal workers, including medical records and any information regarding immunocompromising conditions.

TYPES OF ANIMAL WORKERS

More than 2 million people in the United States are engaged in a wide range of occupational activities that involve animals.¹ These include approximately 750,000 persons involved with livestock confinement; 500,000 involved with dairy farming²; 200,000 workers employed in animal care and services as kennel attendants, groomers, stable hands, zoo keepers, and animal trainers³; and 125,000 researchers and animal handlers involved with laboratory animal research.⁴ Globally, as much as 49% of the world’s population is estimated to be involved in agriculture, which often involves animal husbandry and animal-associated health risks.⁵ Some of these workers are formally employed in full-time positions in animal-related care and may receive preventive health services (such as described in this chapter) through their workplace. However, many individuals who work part-time or full-time with animals may receive little or no preventive health services related to their work exposures. For example, staff at pet swap meets, pet store employees, volunteers at zoos and county fair animal exhibits, wildlife rehabilitators, wildlife biologists, volunteer animal rescue workers, individuals engaged in home slaughter of animals for family consumption, and subsistence (bushmeat) hunters may all face significant “occupational” health risks related to their contact with animals, yet may never receive preplacement examinations, prophylactic vaccinations, or follow-up surveillance examinations to prevent or detect work-related disease. If they do see a medical provider for care of a work-related injury or illness, that medical provider may not be aware of the range of health risks these workers face, and therefore the treatment or recommendations for prevention may not be optimal.

OCCUPATIONAL HEALTH APPROACH

The majority of occupational health services in the United States are provided by family physicians and other clinicians without specialized training.⁶ However, when using a team approach these individuals can learn to provide adequate occupational health services to animal workers.

The components of an occupational health approach are simple and adaptable to a wide range of work settings. They involve identification and control of hazardous exposures, medical services such as careful screening of workers at baseline, vaccination, surveillance of workers’ health, identification of sentinel health events, and management of necessary work restrictions and work-related problems. Although such preventive services may be viewed by some employers as an unnecessary expenditure of resources, they can be cost effective in the long run by preventing potentially compensable work-related illness and injury and promoting worker well-being. Box 12-1 illustrates this approach.

OCCUPATIONAL HEALTH TEAM

Because of the diversity of the hazards encountered by animal workers, providing effective occupational health services to such workers is best accomplished through a team approach. Such a team can include a medical provider to provide screening and management of medical problems, a veterinarian who is familiar with zoonotic disease risks, industrial hygienists to identify and evaluate hazardous exposures and help devise engineering and work practice controls to reduce them, and biosafety/infection control specialists to focus on zoonotic disease transmission risks. Figure 12-1 diagrams the ideal components of an occupational health team that provides preventive health care to animal workers.

Figure 12-1 Occupational health team for animal workers.

Actively involving a designated human health care provider in an occupational health approach for animal workers also has many advantages. Such involvement can lead to the medical provider becoming more knowledgeable about the specific health risks faced by animal workers. Ongoing communication between the medical provider and the veterinarian helps ensure that injured workers are properly managed, workers at increased risk of illness (e.g., immunocompromised persons) and injury are adequately counseled, and preventable hazards in the workplace are identified and addressed.

Veterinarians can play key roles in an occupational health team. The veterinarian is the source of knowledge about relevant animal diseases and the necessary procedures of animal handling and typically has regular contact with the animals, the workplace, and the animal workers. In animal research facilities, the veterinarian is often the administrative supervisor of the animal care workers. In veterinary hospitals the veterinarian may be both the chief clinician and the practice director. For wildlife rehabilitation facilities, animal shelters, zoos, and many other settings, the consulting veterinarian may be the principal point of contact with the medical providers as well as the chief source of medical information about occupational health and safety hazards of the workplace. The veterinarian may be the health professional who is most familiar to the workers and with whom the workers have established a trusting relationship. The veterinarian may also be in regular contact with the employer or worksite supervisor and be able to advocate for the provision of occupational health services for the workers. For all these reasons the veterinarian may be the most appropriate professional to assemble and help lead the occupational health team as well as ensure that the services provided to workers are appropriate for the work setting.

Industrial hygienists have training in the identification and engineering control of a wide range of workplace hazards, including chemical, physical, and biological agents. Consultation from such individuals can help an occupational health team design safe strategies for the handling of hazardous chemicals such as cleaning agents and anesthetic gases, control of noise, and methods to reduce dust exposures that can cause allergy and infection.

Infection control and biosafety specialists are professionals who specialize in the prevention of infectious disease transmissions in workplaces and other settings. They can play a consulting role in the occupational health team by identifying specific infectious disease hazards and helping design strategies to reduce both animal-animal and animal-human transmission of disease. This may involve the design of ventilation systems and work policies such as disposal of infectious waste and use of personal protective equipment.

HAZARD IDENTIFICATION

Animal workers face a wide number of potential occupational health hazards that can be classified as biological, chemical, physical, or psychosocial. These hazards and their control are listed in Table 12-1.

TABLE 12-1 Occupational Hazards Encountered by Animal Workers and Relevant Hierarchy of Control Strategies

Biological Hazards

Allergens

As discussed in Chapter 7, many animal proteins are potential allergens in human beings. Although guinea pigs, mice, rats, and cats are common causes of allergy, virtually any species, including primates, larger domestic animals (such as horses and cattle), and reptiles can also pose an allergic risk to workers.^7,⁸ Exposure to insects such as roaches, flies, and mites as well as insect parts, shellfish (e.g., snow crabs, king crab, lobster, shrimp, scallops), and fish species (e.g., salmon, trout, pilchard, anchovy, hake) has also been associated with allergic reactions.⁹ Other animal-related sources of allergens in the workplace include molds and thermophilic bacteria that infect animal foods (including hay and prepared animal food) and cause asthma, rhinitis, dermatitis, and hypersensitivity pneumonitis.¹⁰

In addition to animal allergens, other allergen exposures for animal workers may include latex gloves, allergenic chemicals such as disinfecting agents (e.g., glutaraldehyde), other cleaning agents and detergents, and organic dusts (e.g., red cedar shavings used as animal bedding).

Not surprisingly, allergic reactions are a well-recognized health problem among animal workers.¹¹ In some settings almost half of animal workers have been reported to develop allergy-related symptoms such as rhinitis, conjunctivitis, asthma, contact urticaria, and other types of allergic dermatitis.^1,^4,^12,¹³ Risk factors for developing allergic responses to antigens include the intensity and duration of exposure to specific antigens^4,¹³ and a history of atopy (allergic predisposition).¹⁴ Allergic exposures can pose a difficult problem for sensitized workers because even low levels of exposure to an allergen may provoke a response in a previously sensitized individual. In addition, personal protective equipment may not adequately protect them from further allergic reactions.

Zoonotic Pathogens

As described in Chapter 9, a large number zoonotic pathogens can pose a hazard to animal workers, who generally have increased exposures to zoonotic diseases compared with the general public. Many of these individual zoonotic diseases with occupational exposure potential are covered in Chapter 9. Selected pathogens of relevance to particular worker groups are described in the sections that follow. For example, occupational cases of Campylobacter and Chlamydophila psittaci infection have been documented among poultry workers^15,¹⁶ and reported human plague cases have been reported among veterinary staff attending to infected cats.¹⁷ With the increasing focus on emerging infectious diseases, it should be remembered that many such diseases appear first or with greatest intensity in the occupational setting. The first recognized (index) human case for the epidemic of severe acute respiratory syndrome (SARS) that began in China was a chef who had extensive exposure to wild game animals in his work.¹⁸ Nipah virus, another deadly emerging viral pathogen, first broke out among Malaysian pig farm workers.¹⁹ Human outbreaks of Ebola virus infection in Africa are believed to originate at least in part from exposures to nonhuman primates and other wildlife during bushmeat hunting and butchering.²⁰ A strain of highly pathogenic avian influenza (HPAI) has caused fatal work-related infection in a veterinarian, and human cases of H5N1 HPAI remain strongly associated with working in animal markets, poultry rearing, slaughtering, defeathering, and preparing infected birds for consumption.²¹ Rift Valley fever, another emerging viral disease, often occurs in human beings as an occupational disease among herdsmen engaged in activities such as assisting with cattle birthing and caring for sick animals.²²

Direct routes of exposure for zoonotic pathogens include a bite or scratch from an infected animal, exposure to infected fluids through splashes to the eye or mucous membranes, touching of contaminated surfaces, needlestick or other sharp instrument injuries, or inhalation of infectious particles in dusts. Vector-borne transmission can also occur in certain workplaces (see arthropod exposures later in this chapter).

In addition to animal-human transmission, some zoonotic diseases can be “reverse zoonoses,” potentially transmitted from human beings to animals in the occupational setting. Examples include tuberculosis, which may be transmitted by human beings to nonhuman primates,²³ elephants,²⁴ and dogs.²⁵

Live Vaccines

Accidental autoinoculation of live vaccines for diseases with zoonotic potential has been reported to result in worker infections. An example is the vaccine for Brucella abortus strain RB51.²⁶ A 1995 survey of veterinarians found that 23% of large animal veterinarian respondents reported accidental self-inoculation with live Brucella vaccine.²⁷

Endotoxin and Organic Dusts

Endotoxin is a biological hazard consisting of lipopolysaccharide compounds from the cell walls of gram-negative bacteria that can grow in animal bedding or feed. When the bedding or feed is disturbed, dusts are generated that can have endotoxin concentrations of 3000 nanograms per meter cubed (ng/m ³), in excess of a proposed guideline² of 9 ng/m³. Adverse respiratory effects such as bronchitis and airway obstruction have been reported in workers who inhale such dusts, especially when working in confined areas with less than adequate ventilation.²⁸ Organic dusts from moldy grain used for animal feed can cause organic dust toxic syndrome (ODTS), a self-limited disease with symptoms including fever, cough, myalgias, headache, and shortness of breath.²

Pathogenic Fungi

A hazard related to work around areas of bird or bat droppings is the exposure to potentially pathogenic fungi including Histoplasma, Cryptococcus, and Blastomyces. Histoplasma capsulatum is a fungus that exists in two forms: a mold form in the soil environment and a yeast form that develops when human beings or other animals inhale or ingest the spores. Although many infected human beings are asymptomatic, some may develop complications ranging from mild flulike illness to chronic lung and eye infections and pericarditis.²⁹ Skin infection can also occur. Immunocompromised individuals are at increased risk of severe disease. The nutrients in bird or bat guano can encourage the growth of spores in the environment. Therefore areas of pigeon and other bird roosting where bird droppings accumulate may be more likely to have high levels of H. capsulatum spores that can lead to inhalation or ingestion by human beings. Poultry litter can also contain Histoplasma spores. Farmers, construction workers, forestry workers, and other workers exposed to disturbed soil or poultry guano can be at risk of infection, especially if individuals are immunocompromised. Unlike birds, bats appear to shed infectious Histoplasma in their droppings. Caves and other areas where bat guano accumulates have been associated with human cases of histoplasmosis.³⁰ The National Institute for Occupational Safety and Health (NIOSH) has published guidelines for reduction of occupational risk of Histoplasma infection that also can be applied to the risk of other fungal pathogens such as Cryptococcus and Blastomyces. These guidelines include the use of respiratory protection, disposable protective clothing and shoe coverings, and gloves that avoid skin trauma to reduce the risk of skin infection. The types of respirators that should be worn during occupational activities with exposures to spore-contaminated dusts depend on intensity of exposure. In low-risk situations (e.g., site surveys of bird roosts), disposable, filtering facepiece respirators may be adequate, whereas extremely dusty work such as removing accumulated bird or bat manure from an enclosed area such as a barn or attic may require full-facepiece, powered air-purifying respirators.³¹

Cryptococcus is another genus of potentially pathogenic fungi found in soil. Like Histoplasma, high concentrations of Cryptococcus spores can be found in soil enriched by bird droppings. Cryptococcus neoformans is found worldwide and can cause significant infections, including meningitis, in immunocompromised individuals. However, C. neoformans has not been extensively associated with occupational or environmental exposures. In contrast, Cryptococcus gatii infection (a species formerly thought to be confined to the tropics) has been tied to environmental and occupational exposures to disturbed contaminated soil in both human beings and domestic animals (including cats, a ferret, and a llama) in North America. In these recent outbreaks, human C. gatii infection has involved both chronic pulmonary manifestations as well as meningitis.³²

Another fungus associated with environmental exposures is Blastomyces, which can cause chronic lung disease in human beings and other animals as well as extrapulmonary manifestations. The typical human case of blastomycosis related to occupational or environmental exposure is a male who works or recreates outdoors where there is wildlife activity. A history of a pet dog with the disease helps support the diagnosis because dogs appear to act as sentinels for environmental exposure risk.³³

Arthropod Exposures

Animal workers may be exposed to ticks, mites, and other arthropods that may be attached to animals or in the vicinity. Such exposures can lead to transmission of zoonotic pathogens as well as bites and allergic reactions. Grain mites are a cause of allergy among agricultural workers.

Chemical Hazards

Exposure to chemical hazards can occur in workers with animal contact, especially among laboratory animal research staff and veterinary workers. Anesthetic gases are a significant risk to veterinary personnel and are discussed below. Other chemicals include immobilizing agents, disinfectants, animal-related pesticides (see Chapter 8), rodenticides, and protocol-specific chemicals in animal research.³⁴ These chemicals can cause a wide range of health effects from skin and mucous membrane irritation to neurological effects and adverse pregnancy outcomes (e.g., miscarriage from anesthetic exposures).³⁵ A Materials Safety Data Sheet (MSDS) on the hazards, safe handling, and exposure management of specific chemicals should be available to all animal workers encountering chemicals in the workplace. Depending on the particular exposure, specific types of decontamination and acute medical care may be needed. In addition, inspection of the workplace should be considered in coordination with the industrial hygienist and other safety personnel.

Farm workers, especially those working in animal confinement facilities with large numbers of animals such as swine, may be exposed to pesticides as well as high levels of ammonia and hydrogen sulfide levels related to animal waste. These irritating chemical fumes can cause toxic chemical pneumonitis and bronchitis.¹⁰ Hydrogen sulfide, produced by decaying organic waste, is a mitochondrial toxin that can cause acute loss of consciousness, respiratory arrest, and death.³⁶

Cattle silage can be a source of nitrogen dioxide toxicity causing “silo filler’s disease,” an acute syndrome characterized by pulmonary edema, respiratory distress, and death in sufficiently high exposures.³⁷

Physical Hazards

Common physical hazards faced by animal workers include bites and crush injuries from animals; acute and chronic musculoskeletal strain from handling animals and equipment; slip, trip, and fall injuries; and, in certain settings, exposure to noise, extremes of temperature, and radiation.³⁸

Psychosocial Stressors

Although there are many psychosocial benefits of human-animal interaction (see Chapter 5), animal workers may face particular psychosocial stressors. These can include fear of attack and injury; fear of infectious disease; emotional reactions to performing euthanasia, necropsies, slaughtering, or other procedures; compassion fatigue³⁹; and professional burnout.⁴⁰

HAZARD CONTROLS

Once workplace hazards are identified, the goal is to reduce exposures to these hazards. Taking an occupational health approach to such hazards involves using a hierarchy of controls that range from most effective to least effective methods to reduce the health risks to workers. This hierarchy is listed in Table 12-2. Many hazards can be eliminated at the source, or a less-dangerous substance or process can be substituted. Engineering controls include physical methods to reduce exposures such as improved ventilation and use of nonporous surfaces on counters that can be easily disinfected. Administrative and work practice controls involve job restrictions for susceptible persons, limiting individual worker exposure times in high-exposure areas, and preventive practices such as hand hygiene. Reliance on personal protective equipment such as gloves, gowns, and respirators is considered to be the least effective and often most cumbersome approach to hazard control.

TABLE 12-2 Hierarchy of Controls for Workplace Hazards

Control Strategy	Effectiveness
1. Eliminate the hazard	Most effective
2. Substitute for the hazard
3. Engineering controls
4. Administrative/work practice controls
5. Use of personal protective equipment (e.g., gloves, masks)	Least effective

Table 12-1 shows examples of such controls for handling biological, chemical, physical, and psychosocial hazards in animal work. Obviously the most effective controls vary by the specific type of hazard, and the occupational health team must consider the most feasible type of control for each particular hazard. Although they may require a greater up-front investment, controls at the top of the hierarchy, such as elimination, substitution, or engineering controls, may be most cost effective at preventing work-related health problems. For example, eliminating a zoonotic disease (such as brucellosis) in an animal population through vaccination and other preventive veterinary care may be more cost effective over time than relying on personal protective equipment such as respirators and gloves for animal workers. Similarly, substituting a less-toxic cleaning agent (see Chapter 8) may be more cost effective in reducing health complaints of eye and throat irritation among exposed workers than the use of gloves and respirators.

OCCUPATIONAL MEDICINE SERVICES

Because not all health hazards in the workplace can be eliminated or completely controlled by the methods listed above, animal workers may require occupational medicine services to prevent and treat work-related illnesses and injuries. Such services may involve both human health care providers and other members of the occupational health team.

Preplacement Screening

Preplacement examination (or post–job offer evaluation) is a medical evaluation conducted to determine if a newly hired worker is able to safely perform the essential functions of the job with or without accommodation. Such examinations can present an ideal opportunity for preventive risk assessment and counseling as well as prophylactic vaccination. However, for many animal workers such examinations are not required by law and may not be provided because an employer believes they are not necessary. Even when animal workers do have such clearance examinations, the service may be provided by a personal physician or other health care provider who is not familiar with the health risks of animal work. As a result, there may be many missed opportunities for prevention.

The content of the preplacement examination can vary depending on the particular job type and set of exposure risks but often involves a screening medical history, physical examination, and diagnostic testing, if indicated, to identify important preexisting conditions that might place an individual at increased risk of injury or illness, including immunocompromising conditions ⁴¹ or history of allergy. A history of previous animal contacts and whether animals are kept in the home may provide useful information. The use of standardized history and physical forms may assist in this process. Figure 12-2 shows an example of an animal worker questionnaire that might be appropriate for a worker in an animal care facility or a veterinary practice.

Figure 12-2 Sample medical questionnaire for animal workers.

If workers will be using respiratory protection involving N-95 respirators or other types of respirators, they should complete the Occupational Safety and Health Administration (OSHA) respirator questionnaire as part of the respirator medical clearance required under the OSHA Respirator Standard 1910.134 (available at http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9783). If latex is used in the workplace, workers should be asked about any previous reactions to latex, including rash, hives, nasal or eye inflammation, breathing difficulties, or anaphylaxis.

In addition to the history and physical, other baseline testing may be indicated. Audiometry at baseline is required by OSHA if the worker will be exposed to noise at levels of 85 A-weighted decibels (dBA) or higher for an 8-hour time-weighted average. Testing of lung function (spirometry) is recommended for individuals with potential exposure to respiratory allergens, including veterinary workers and workers in animal facilities. Allergy testing is not usually performed routinely at baseline but may be warranted if the history suggests sensitization to particular allergens found in the work setting. In certain settings baseline serology or serum banking may be indicated to detect immunologic response to zoonotic pathogens.

Based on the findings of the preplacement examination, the medical provider can perform a risk assessment for the individual and decide whether the individual can safely do the job with or without accommodation. To do this, the medical provider may need to consult a veterinarian, biosafety professional, or other members of the occupational health team to learn more about specific risks of the job. For example, a person with valvular heart disease may need to be restricted from working in a research facility with pregnant sheep because of the risk of Q fever. A worker who developed allergy to mice or rats in a previous job may need to be restricted from future contact with such animals. In discussing disease risks with other professionals, it is important (although sometimes a challenge) to keep medical information about the worker confidential and prevent possible workplace discrimination because of a medical condition. If work restrictions are necessary, they can be indicated on a work status form that can be given to the employer to outline such restrictions without revealing confidential health information about the employee. In general, confidential health information on employees should not be shared with the employer, supervisor, or other management personnel by the human health clinician evaluating the worker.⁴²

Vaccinations

A number of preventive vaccinations may be indicated for animal workers. Previous vaccination history should be assessed at the preplacement evaluation and the need for additional vaccination determined. As with other aspects of the preplacement risk assessment, consultation with a veterinarian may be advisable or clear instructions conveyed to the health care provider regarding necessary vaccinations. All animal workers should be up to date with respect to tetanus vaccination. Table 12-3 lists vaccines to consider for particular groups of workers. Rabies vaccination is indicated for a number of workers.⁴³ Table 12-4 shows recent recommendations for which individuals should receive preexposure rabies vaccine.

TABLE 12-3 Occupational Medicine Services for Animal Workers

Category of Medical Service	Specific Medical Services Indicated	Types of Animal Workers Requiring Occupational Medicine Services
Preplacement screening	Questionnaire regarding immune compromise, musculoskeletal problems, pets and other animal contacts Physical examination	All
	Respirator clearance questionnaire, spirometry	Workers exposed to respiratory hazards, workers who will be using respirators
	Audiometry	Noise-exposed workers
	HIV and TB screening	Animal research and workers in contact with nonhuman primates
	Consider serum banking	Zoological, wildlife, or research workers; others with zoonotic exposures
Vaccination	Rabies	See Table 12-4
	Tetanus (every 10 years)	All
	Annual influenza vaccine	All (especially poultry and swine workers)
	Anthrax	Laboratory workers routinely working with concentrations of anthrax or aerosol potential⁸⁷
	Q fever (consider)*	Laboratory workers, researchers working with pregnant sheep, slaughterhouse workers⁷⁰
	Hepatitis A and B, measles, polio	Workers in contact with chimpanzees and other nonhuman primates
Training	Veterinary standard precautions, anesthetic safety, bite and injury prevention, OSHA training, safe chemical handling	All
Medical surveillance	Periodic questionnaire about allergy/respiratory symptoms	NIOSH recommendations in all animal workers with allergen exposures
	Reassess zoonotic disease risk	All animal workers with change in medical status
	OSHA respirator questionnaire; spirometry; further evaluation in positive responses to questionnaire	Workers using respirators
	TB testing (skin test or interferon assay)	Animal workers with nonhuman primate and/or elephant contact (see Figure 12-2)
	Annual audiometry	Workers with noise exposures ≥85 dBA (8-hour average)
Acute injury and illness management	Treat acute problem, determine if work related, identify sentinel health events indicating problem with hazard control and risk to other workers and/or patients Consider whether human being with a zoonotic disease is a sentinel for animal health problem as well as indicator of occupational risk to other workers Determine source of infectious exposure and consider prophylactic treatment for exposure (e.g., rat-bite fever, leptospirosis)	All
Acute injury and illness management	Herpes B exposure prophylactic treatment⁶⁵	Workers with exposure to nonhuman primates
Confidential medical record management	Protect confidentiality of medical records	All

HIV, Human immunodeficiency virus; TB, tuberculosis; OSHA, Occupational Safety and Health Administration; dBA, decibels (acoustic).

* Not commercially available in the United States. Persons wishing to be vaccinated should first have a skin test to determine a history of previous exposure. Individuals who have previously been exposed to C. burnetii should not receive the vaccine because severe reactions, localized to the area of the injected vaccine, may occur.

TABLE 12-4 Rabies Preexposure Prophylaxis Guide

Training

Training at the time of job entry is recommended by the National Association of Public Health Veterinarians (NAPHV) for workers in veterinary facilities ⁴¹ and is relevant for other animal workers as well. Aspects of such training include education about zoonotic disease risks, infection control practices, use of personal protective equipment, safe chemical handling techniques, and injury prevention, with emphasis on proper animal handling, restraints, and recognition of behavioral cues in animals. Such training should be provided by an individual familiar with the risks of a particular workplace and the safety policies in place, such as a safety officer. Training should be documented. Follow-up training in health and safety can take place on a regular basis with animal workers to identify and mitigate hazards, address institutional occupational health policies (including record keeping), address personal hygiene, provide points of contact for more information or for when to seek medical attention for work-related problems, review unit inspection standards, and evaluate future training needs.